The invention relates generally to laser devices and, in particular, to a laser beam delivery system.
A laser beam diverges as the beam is sent from the laser source. Consequently, laser delivery systems use collimators to adjust the divergence of the beam. Generally, a collimator adjusts laser light to produce parallel rays of light. The collimator also can control the beam spread, so that the desired beam size occurs at the focusing element.
Low power laser systems tend to use collimator lenses to collimate laser beam. The Walden U.S. Pat. No. 3,710,098 and the Hill U.S. Pat. No. 3,407,294 disclose methods of delivering laser light using lenses. Both patents disclose methods of moving the lenses to vary the divergence of the output beam.
Higher power lasers tend to use reflective collimators to collimate the laser beam. The Paz U.S. Pat. No. 5,020,906 discloses a reflective collimator using either a single spherical mirror or a parabolic mirror. The Stewart et al. U.S. Pat. No. 3,541,323 discloses a parabolic mirror to project a laser beam. The Stewart patent further provides for adjusting the divergence of the output beam with a variable expanding optic system such as zoom optics.